exhaust gaskets

[madaca]

ok, so I finally got the vacuum leak from the carbs sealed tight. I bought a better gasket and it seemed to have worked. I am still having trouble getting the truck to run smooth. It sputters like crazy and backfires if I give it gas and every once in awhile it will smooth out. I am noticing air popping where the manifold meets the exhaust pipe. I believe I may need to change that gasket and might as well change the manifold gaskets as well. Does anyone think this will help the truck to run right? Could this be the cause of it sputtering? What about changing out the spark plugs. Maybe I should get new plugs and see if that solves the problem. Any help appreciated.